Process and composition for improving the mechanical properties of flameproofed cellulosic textile materials



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PROCESS AND COMPOSITION FOR IMPROVING THE MECHANICAL PROPERTIES OF FLAME- PROOFED CELLULOSIC TEXTILE MATERIALS Claude Jean Michel Senez, Chantilly, France, assignor to Etablissements Kuhlmaun, Paris, France No Drawing. Filed Feb. 27, 1964, Ser. No. 347,677 Claims priority, application France, Mar. 1, 1963, 926,524 3 Claims. (Cl. 117-136) The present invention concerns improvements in the treatment of cellulosic textile materials. The expression textile material is meant to include not only fabrics but fibres and yarns. j

A class of flameproofing substances for cellulosic textile material exists which may be obtained for example by careful hydrolysis of the reaction products from ammonia and phosphonitrile chlorides or by the action of ammonia and methyl alcohol on phosphonitrile chlorides. The phosphonitrile chlorides may be those of the empirical formula (PNCI or those of the emperical formula wherein n is an integer greater than 1. Such flameproofing substances are described, for example, in United States Patents Nos. 2,782,133 and 3,012,908, in application No. 281,057 of May 16, 1963, and in application No. 267,914 of Mar. 26, 1963, now United States Patent No. 3,193,571. These substances, which will hereinafter be called aminated flameproofing substances derived from phosphonitrile chlorides, impart to cellulosic fibres a resistance to fire which is unimpaired by several washings. The heat treatment necessary to fix them on the fibre, however, causes a weakening of the mechanical properties of the fibre, like all treatments for modifying cellulose. This weakening is more or less important according to the type of flameproofing substance used, the percentage of the substance contained in the treatment bath, the method of application and the conditions of the heat treatment. It is very desirable that the diminution in the mechanical properties should be as small as possible.

It has now been found, according to the present invention, that without modification of the fastness to washing of the flameproofing finish obtained by means of the aminated flameproofing substances derived from phosphonitrile chlorides, the loss of resistance to tearing is decreased, possibly even the resistance of the material to abrasion is increased. The results obtained according to the present invention, described below, are surprising because polyethylene is very combustible and the presence of fatty or waxy substances on the cellulosic fibres generally has the effect of accelerating their combustion.

According to the present invention therefore a process for flameproofing cellulosic textile material is provided which comprises impregnating the material in an aqueous bath containing an aminated flameproofing agent derived from a phosphonitrile chloride and an aqueous dispersion of polyethylene, and subjecting the material thus impregnated to a heat treatment. The invention also includes the novel treatment baths containing an aminated fiameproofing agent derived from a phosphonitrile chloride and an aqueous dispersion of polyethylene. The cellulosic textile material may be for example natural material such as cotton or regenerated material such as viscose.

To obtain the desired efiect, it is sufiicient to add a small amount of the polyethylene dispersion to the bath, for example 2 to 20 grams of polyethylene per litre of treatment bath. The temperature of the heat treatment is advantageously between 120 C. and 230 C. In addition to the flameproofing agent and the dispersion of polyethylene, the treatment bath may contain any auxil- 3,323,944 Patented June 6, 1967 iary products intended to facilitate the penetration of the bath into the material, to increase the flameproofing effect, or to bring about other effects, such as for example, antifungal efiects, waterproofing or proofing against oil.

5 The following examples, in which the parts are parts by weight, are purely illustrative and do not limit the invention.

Example 1 An aqueous bath is prepared containing, per litre, 350 grams of the aminated flameproofing agent described in Example 2 of US. Patent 3,012,908, 70 grams of urea and 35 grams of a 17% aqueous dispersion of polyethylene of melting point 97.8100 C. A cotton twill fabric well boiled, weighing 330 grams per square metre is padded in this bath, is squeezed out, so that the amount removed is 80%, and is dried in an oven at 80 C., fixed for 5 minutes at 150 C. in an oven, rinsed in tepid water and again dried at 80 C. A fiameproofed fabric is obtained which has the same resistance to tearing as untreated fabric, and which remains flameproof after washes at the boil in a bath containing, per litre, 2 grams of sodium carbonate and 5 grams of Marseilles soap.

Example 2 An aqueous bath is prepared containing, per litre, 350 grams of the aminated flameproofing agent described in Example 1 of US. patent application No. 267,914, now United States States Patent No. 3,193,571, 70 grams of urea, and 70 grams of a 15% aqueous dispersion of polyethylene of melting point 97.8100 C. A cotton twill fabric well boiled, Weighing 330 grams per square metre is padded in this bath, is squeezed out so that the amount removed is 80%, and is dried in an oven at 80 C., fixed for 5 minutes at 150 C. in an oven, rinsed in tepid water and again dried at 80 C. A fiameproofed fabric is obtained which has the same tearing resistance as the untreated fabric, and which remains fiameproofed after 10 washes at the boil in a bath containing, per litre, 2 grams of sodium carbonate and 5 grams of Marseilles soap.

Example 3 An aqueous bath is prepared containing, per litre, 350 grams of the aminated flameproofing agent described in Example 5 of US Patent 3,012,908, grams of urea and 17.5 grams of a 16% aqueous dispersion of polyethylene of melting point 97.8 C. A cotton twill fabric well boiled is padded in this bath, is squeezed out so that the amount removed is 80%, and it is then dried in an oven at 80 C., fixed for 5 minutes at 150 C. in an oven, rinsed in tepid water and again dried at 80 C. A fiameproofed fabric is obtained, the loss of resistance to tearing of which is only 7%, although, if the polyethylene dispersion is eliminated from the treatment bath, the loss of resistance to tearing is 25%.

I claim:

1. In the treatment of cellulsoic textile material with an aminated flameproofing agent derived from a phosphonitrile chloride the improvement which comprises impregnating the material in an aqueous bath of the flameproofing agent containing an aqueous dispersion of polyethylene, said polyethylene being present in an amount sufficient to prevent loss of resistance to tearing of the ifi/fl-arneproofed cellulosic textile material, the amount of polyethylene being from 2 to 20 grams per litre of bath,

and subjecting the textile material to a heat treatment between C. and 230 C.

2. In the treatment of cellulosic textile material with 70 an aminated flameproofing agent derived from a phosphonitrile chloride the improvement which comprises impregnating the material in an aqueous bath of the flameproofing agent containing an aqueous dispersion of polyethylene, said polyethylene being present in an amount suflicient to prevent loss of resistance to tearing of the fiameproofed cellulosic textile material, the amount of polyethylene being from 2 to 20 grams per litre of bath, squeezing out the impregnated material so that 80% of the impregnant is removed therefrom, drying and subjecting the material to a heat treatment between 120 C. and 230 C.

3. An aqueous bath consisting essentially of an aminated flameproofing agent derived from a phosphonitrile chloride and an aqueous dispersion of polyethylene, the

amount of polyethylene in the bath being from 2 to 20 grams per litre of bath.

References Cited UNITED STATES PATENTS 2,782,133 2/1957 Vallette 117-138 3,012,908 12/1961 Bilger l17137 3,245,831 4/1966 Shippee 1l7139.5

10 WILLIAM D. MARTIN, Primary Examiner.

T. G. DAVIS, Assistant Examiner. 

1. IN THE TREATMENT OF CELLULOSE TEXTILE MATERIAL WITH AN AMINATED FLAMEPROOFING AGENT DERIVED FROM A PHOSPHONITRILE CHLORIDE THE IMPROVEMENT WHICH COMPRISES IMPREGNATING THE MATERIAL IN AN AQUEOUS BATH OF THE FLAMEPROOFING AGENT CONTAINING AN AQUEOUS DISPERSION OF POLYETHYLENE, SAID POLYETHYLENE BEING PRESENT IN AN AMOUNT SUFFICIENT TO PREVENT LOSS OF RESISTANCE TO TEARING OF THE FLAMEPROOFED CELLULOSIC TEXTILE MATERIAL, THE AMOUNT OF POLYETHYLENE BEING FROM 2 TO 20 GRAMS PER LITRE OF BATH, AND SUBJECTING THE TEXTILE MATERIAL TO A HEAT TREATMENT BETWEEN 120*C. AND 230*C. 